USRP frequency measurement

[mathias19100]

hello everybody,

I am working on a project with USRP (USRP2930) and i would like to measure a frequency.

So, In my project, my USRP Card 2930, is in reception (RX) and i gernerate a signal with signal generator.

I want to measure with my usrp card the carrier frequency that I generate. is it possible? can you help me please ?

in the drivers, each time it is necessary to inform the frequency of the expected signal, but I want to measure this frequency and not to tell the usrp that the signal is at this carrier frequency.

Thanks you

Mathias

[Cdkey]

Hello mathias19100,

You could calculate the FFT of the incoming signal and do a peak detection to get the carrier frequency.

Have a nice day!

Clement

[mathias19100]

thanks you Clement for your answer, i am going to try.

But I do not want to say to the card: the signal is at X Hz. the block "configure signal" is it essential for the proper operation of the card? I have the impression that yes, and therefore it is mandatory to enter a carrier frequency to configure the card.

have a nice day

Mathias

[max_str]

Hey Mathias

yes you need to set a carrier frequency, at least a rough one depending on the bandwidth you use for recording your signal. You could also sweep over a frequency range.

But you should also be aware, if you try to search for a real frequency (pure sine) using a FFT, that the FFT will show you the frequency twice, above and below of your carrier.

Max